4 Answers
4

I am not sure if there is a definite list you can prepare with regards to the features you need to check for but here is a list I would use:

Is the objective of the web app clear : Let's assume you are designing a web app to show financial information of the latest stock trades. Is that information apparent at first when you look at the web app or is there any disconcerting information which is distracting the user from the focus of the app.

Are all the goals of the app satisfied : This point is a continuation of the previous point. In this point I would recommend establishing all the goals which the app has set out to do are satisfied or not and if they are not satisfied, what are the unique cases in which the app fails and if we should consider those unique cases or not.

Is the user able to navigate to the content in the app without knowing any shortcuts : Though it is always useful to incorporate shortcuts not all users would be aware of them and there must be a easy and intutive way for users to navigate to the content in the app without having to know specific shortcuts.

Have visual design standards been followed to ensure the app is readable and understandable : Though you might have fantastic content if your design standards are not good, you might end up with an app which is really unreadable and difficult to comprehend. Hence check if your design standards enable users to use your under a number of different circumstances (also check for potential cases like color blindness or where the user might need larger text to understand the content on the app). Also ensure that your visual guidelines enforce your branding guidelines and keep a consistent design throughout

Check for Accessiblity : Though it might not be a requirement in your country to check for accessibility, it is always a good thing. Check the W3C standards on accessibility for more information

Check if your app has a consistent navigation layout : Ensure your app has a consistent navigation layout which is common across all the pages of the app leading to little or no confusion about the sudden change in navigation. Also ensure users can quickly jump from one section to another easily without having to find their way around.

Check for content correctness : The easiest way to lose trust is by providing incorrect or badly structured content. Check if your content is correct and reads well.The referenced article states content strategy as:

Check for Browser/platform compatibility : Since you are going to be creating a web app ensure there is browser compatibility with all major browsers and potential browsers your users might use.If you feel that there is a also scope for the app to accessed through mobile devices, ensure your app scales well to those platforms too.

Check for load testing to ensure your app can stand up to user requirements in cases of heavy loads

Check for security to ensure there is no scope of malicious scripting

Check to ensure that all your links work well :If any of your links lead to a dead page or a 404 page, ensure the user has a way to get back from there or navigate from that place to another point in the site. This question about how to create a 404 page will help

As others commented it does seem to be pretty late to address UX issues before the release. What you can try doing now is define a list of realistic tasks that your users will be trying to do and inspect the UI flow against the tasks. For example (assuming the site is for traveling): Oliver will be traveling from London to Paris next week; he needs to purchase an airplane ticket for the flight that leaves early in the afternoon between Wednesday and Friday. Now go to the site and perform this task trying your best being a user that doesn't know the inter-workings of your site. While doing the task take notes at any point anything is confusing, you are stuck, information you are looking for is not presented, etc. Having a realistic scenario in mind can help you uncover the issues that could be addressed in the future releases. If your company has product owners/managers assigned to the project you may want to talk to them to learn about the customer goals for the site.
That is not the ideal process but doing something to catch UX issues is better than doing nothing :)

Mervinj made a good point, that you're basically just doing a heuristic evaluation. There are a few methods out there, but the most common one is Nielsen's heuristics. I always keep a copy printed out on my wall to check as I design a first draft.